Pressure-relief valve



May 27, 1930. R. E. .JOYCE PRESSURE RELIEF VALVE Original Filed Sept. 2,1927 Patented May 27, 193

UNITED STATES ROY E. JOYCE, OF LOS ANGELES, CALIFORNIA PRESSURE-RELIEFVALVE p Application led September 2, 1927, Serial No. 217,203. RenewedMarch 22, 1930.

In pressure relief valves now in use, the customary spring or weighteXerts a holding force on the valve equivalent only to the differencebetween the normal pressure held back by the valve and the pressure atwhich it opens. For instance, in a line to carry twenty-tive poundspressure, this pressure mustnotexceedt vcnty-eight pounds. Hence, theeffective force of the spring or weight which holds the valve closed, isbut three pounds and this is insutlicient to hold the valve againstleakage. My invention however, aims to provide a new and in'iprovedrelief valve embodying eiiicieiit means for multiplying this effectiveforce of the spring or weight so that while many times that force willbe exerted to hold the valve closed, such force will be overcome by thesame pressure increase which would now be relied upon to open the valve.

With the foregoing in view, the invention resides in the novel subjectmatter hereinafter described and claimed, the description beingsupplemented by the accompanying dra 7ing.

Fig. 1 a vertical sectional view of a relief valve constructed inaccordance with my invention.

Fig. 2 is a 'vertical transverse sectional view on line 2 2 of Fig. 1.

Fig. 3 is a horizontal sectional line 3--3 of Fig. 1.

rEhe drawings above briefly described, illustrate the preferred form ofconstruction and while this construction will be herein specificallyexplained, it is to be understood that within the scope of the inventionas laimed, variations may be made.

The numeral 5 on the drawing, denotes a valve casing having a pressureinlet 6 at any desired location. One side wall of the casing 5 is formedby a diaphragm 7 held in place by bolts 8 and a bonnet 9. 10 denotes apressure outlet opening through the wall of the casing, the axis of thisopening being at right angles to the axis of the diaphragm or movablev/all 7. At the periphery of this opening, an inwardly or pressurefacing seat 11 is provided, said seat being here shown as formedV on aseparate outlet connection 12 view on which is secured to the casing bycap screws or the like 18.

A valve le is slidably mounted in the opening 10 for co-action with theseat 11 and either the periphery of this valve or the wall of saidopening, are longitudinally ribbed as at 15 to permit fluid toA passwhen the valve is open. t

Two toggle links 16 and 17 vare pivoted together at their inner ends asdenoted at 18, the outer end of link 17 being pivoted at 19 to lugs 19integral with the portion of the casing 5 opposite the inner end of thevalve 14, while the outer end of link 16 is pivoted at 20 in a kerf 20formed in said inner endof said valve. These links 16-17 conniergetoward the diaphragm 7 and are connected with the latter by an actuatinglink 21,'one end of this link being pivoted to thev links 16-17 by meansof the pivot 18, while suit-v able pivot means 22 connects the other endof said actuating link with the diaphragm 7.

A coiled compression spring23 is housed in the bonnet 9 and exertsinward pressure on he diaphragm 7 so as to hold the links 16-17 -21, invalve-closed position as shown in vF ig. 1. The strength'of the spring23 may be varied by means ofan appropriate adjusting screw 24 and whilethe valve may be set to blow-olf at any desired increase in pressure,the spring and the toggle links will nevertheless eXert a force manytimes that which is ordinarily obtained in pressure relief valves forthe purpose of holding the valve closed. A horizontal ledge 17 a isformed integrally with the casing 5 between the lugs 19a and the opening10. This ledge is in the downward path oflink 17 and prevents this linkand link 16 from moving downwardly past dead center, excessivelycompressing the soft valve face 14a and then edecting opening of thevalve at low pressure.

I claim:- I

1. A pressure relief valve comprising an open-topped casing having apressure inlet and a lateral pressure outlet, the latter havinganinwardly facing valve seat and valve-guiding means, a valve slidablymounted in said guiding means and co-operating with said seat, twotoggle links in the casing having Ament of said toggle links.

their inner ends pivoted together, the outer end of one o1E said linksbeing pivoted to said valve, the outer end of the other link beingpivoted tothe casing at a point horizontally spaced from the inner endof said valve, a horizontal ledge in the casing formed integrally withthe latter in the downward p path of said other link to limit thevalve-closing movement of the two toggle links, a vertical link pivotedat its lower end to the inner ends of said toggle links,adiaphragmlextending across the open top of the casing and having a lugpivoted to the upper end ofsaid Yvertical link, a hood .secured to thecasing over said diaphragm, a coiled compression spring in said hoodacting downwardly on said diaphragm, and an adjustingscrew for saidspring threaded through said hood.

.2. .A..pressure relief valve comprising an op'en-.toppedeasing having apressure inlet at its lower end. and a lateral pressure outlet, saidoutlety embodying an .inner .cylindrical longitudinally ribbed portionand an inwardly acing'valve seatlat lthe outer end of said cylindricalportion7 V.a .lug in .said casing formed integrally Vtherewith opposite.said pressure'outlet, a .horizontal ledge in ,said casing formedintegrally .therewith between said lug and said pressure outlet, acylindrical soit-faced valve slidable insaid cylindrical portion ofsaidpressure outlet in contact with the ribs thereof,fsaid valve havinga recess in its inner end,.two toggle links in the casing pivotedtogether at their inner ends, the outer end of one of' said togglelinksbeing pivoted to ,said` lug, the outer end .of the other link beingdisposed in said. recess of'said valve and pivoted to the latter, avertical link pivoted at its lower endv tothe innerends of saidtoggle.links, aldiaphragm across the open vtop of the casing having alug pivoted to the upper'endof said verticallink, a hood secured to thelcasing over said diaphragm, a coiled compression spring A' in said hoodacting `downwardly on said diaphragm, and an adjusting screw for .saidspring threaded throughfi said hood, the aforesaid ledge being disposedin thefdownwardpath of one of the toggle links tolimit the valve-closingmove- In testimony whereof I have hereuntoafvliked my signature.

ROY E. JOYCE.

